The Moths of the British Isles/Chapter 11

Authors are not at all agreed as to the systematic position of this family, and there seems to be some difference of opinion as to the species that properly belong to it. Sir George Hampson has transferred the group to the Noctuidæ and separated S. revayana from the others, placing it in his sub-family Sarrothripinæ, to which also belong certain Indian species.

Only four species occur in our islands. Three of these have green fore wings and pale grey or whitish hind wings. The other species, Sarrothripa revayana, has the fore wings of various shades of grey, brown, or blackish; its boat-shaped cocoon is very like a small edition of that of Hylophila bicolorana, and, although the caterpillar is in some respects not very dissimilar to those of the green-winged species, the moth does not seem quite to be one of their set.

In size, colour of the fore wings, and general appearance this moth might be mistaken for the much more common Green Tortrix (Tortrix viridana). On examination however, it will be seen to have white hind wings, whilst those of the Tortrix are grey. Again, the head, front of thorax, and front edge of the fore wings are white in the present species (Plate 73).

The caterpillar is green, inclining to whitish on the back, the latter lined with brownish, and bearing warts on rings six and eleven. It feeds in July and August on the terminal leaves of osier and willow; these leaves are drawn together with silk, and the solid appearance of the foliage at the end of the twig will afford a clue to the probable whereabouts of the caterpillar when one is searching for it. Chrysalis, brown, darker on the back, paler on the under parts, and on the wing covers; enclosed in a tough boat-shaped cocoon which is often constructed on the bark of a twig or stem of the food plant. As a rule the moth does not emerge until the following year, but in some years a few will appear in the autumn, and others remain in the chrysalis until the following May or June.

This species inhabits damp places where there are osiers, and it is especially common in the fens. It occurs in most of the southern and eastern counties of England, but does not seem to be recorded from other parts of the British Isles.

The bright green fore wings are crossed by two shaded silvery lines, and a narrow silvery band, the latter running from the tip of the wing to the inner margin, and usually there is a whitish shade between the two lines; the fringes are reddish, or pinkish, and the front and inner margins are tinged with the same colour, sometimes strongly so on the inner margin. The hind wings of the male are whitish, tinged with yellowish green; fringes white, more or less tinted with reddish; in the female the hind wings are entirely silky white. Antennæ reddish (Plate 73).

Caterpillar, green, with yellowish dots, lines on the back, and edging to first ring of the body; the anal claspers are marked above with red. It feeds in August and September on the leaves of oak, birch, beech and nut (Plate 72).

The chrysalis is purplish above merging into pale brown beneath; wing-cases ochreous brown; the dorsal surface, especially the ring divisions, are dusted with whitish dots. It is enclosed in a papery cocoon of a pale pinky brown colour; frequently spun up on the back of a leaf, but also in a curled leaf, bark chink, or among herbage and litter on the ground.

The moth flies in June and July, and is not uncommon in woods throughout the greater part of England, it may be beaten from trees, and is often to be seen sitting on bracken and other undergrowth. It is also found in Scotland up to Moray, and seems to be pretty generally distributed in Ireland. The range of this species abroad extends through Northern and Central Europe, South Russia, Siberia, to Japan.

The green colour of the fore wings of this moth is rather paler than of those of the last species; they are crossed by two almost parallel yellowish lines; hind wings white and silky. Antennæ whitish towards the tip and reddish towards the base (Plate 73).

Caterpillar green, sometimes tinged with yellow, a dark line along the middle of the back is edged on each side with whitish.

The chrysalis is pale greenish, with a narrow black stripe from the head along the thorax extending to the fourth abdominal ring; the wing cases reach the sixth ring, which together with the back of the fifth are roughened with fine blackish points.

Cocoon boat-shaped with the keel raised at the head end. When the moth emerges from this end the cocoon closes up tightly again, so that no opening is to be seen; slight pressure on the back will cause the exit slit to open.

This rather local species is perhaps commoner in the eastern counties of England than elsewhere, but it occurs in the oak woods of Berkshire, and southward to Kent and Hampshire. Much scarcer in the west and midlands, and apparently unknown in the north. Barrett gives Galway and Queen's County in Ireland, but adds that it is rare.

Distributed over Central and Southern Europe, and its range extends to South Sweden, and Asia Minor.

This is a most variable species, ranging from greyish white through various shades of brown to blackish; the grey and the brown forms are sometimes tinged with green. In the illustration some of the more usual forms of marking are shown. 1 (more or less typical) and 2 are the most common; 5 (ramosana) is less frequently met with; 4 (ilicanus) has ashy brown fore wings with a black bar at the base, three black dots on the disc, and a series of black dots before the outer margin, the triangular marking on the front margin is reddish; 3 is a modification of the typical form approaching var. dilutana; 6 is of the afzelianus form, with shiny brownish fore wings and black markings.



The caterpillar is green with whiter ring divisions; a few long whitish hairs on each segment; a faintly darker line along the back, and a paler interrupted line along the sides. Head yellowish green marked with brownish and sparsely clothed with whitish hairs. It feeds in June and July on the leaves of oak and sometimes on sallow. It spins a whitish boat-shaped cocoon on the under side of an oak leaf or twig, and therein turns to a pale green chrysalis with a broad purple brown stripe along the back from the head; the blunt last ring is tinged with purplish brown and the edge of the ring immediately before it is fringed with minute hooks (Plate 72, Figs. 4, 4a).

The moth seems to be out from August to April. It may be beaten from trees and bushes throughout the autumn, and during the later months of the year it seems to hide in yews and hollies. Just before dusk it becomes active and may then be netted as it flies; later on it may be seen regaling itself on overripe blackberries, or on the ivy blossom, and it is not an infrequent visitor to the sugar patch.

The species has been found in almost every part of England and Wales wherever there are oak woods. In Scotland it occurs up to Argyllshire and Moray. For Ireland, Kane gives Tyrone, Westmeath, Galway, Kerry, and Limerick.

Distribution abroad: Central and Southern Europe, extending northwards to Scandinavia, and eastwards to Amurland and Japan.